TSAR Nicholas I 6 July O. 25 June 1796 - 2 March O. 18 February 1855 was Emperor of Russia, King of Congress Poland and Grand Duke of Finland. He was the third son of Paul I and younger brother of his predecessor, Alexander I. Nicholas inherited his brother's throne despite the failed Decembrist revolt against him.
He is mainly remembered in history as a reactionary whose controversial reign was marked by geographical expansion, economic growth, and massive industrialisation on the one hand, and centralisation of administrative policies and repression of dissent on the other. Nicholas had a happy marriage that produced a large family; all of their seven children survived childhood.